Transcript for US Army Vet Allegedly Fights Alongside Al Qaeda in Syria

late news, reports that a u.S. Army veteran from phoenix, arizona, is under arrest tonight and charged with joining forces with al qaeda, taking up arms in syria. Who could this man be? Abc's david kerley has that. Reporter: Eric made no secret what he was doing in syria. He posted it on facebook. The former u.S. Army soldier was fighting against the syrian regime, but he was fighting with a group the u.S. Considers terrorists. . Reporter: He entered syria in january and linked up with al qaeda I iraq. U.S. Officials interviewed him more than once when he returned to turk toe acquire weapons. Turg to the complaint filed against him, he admitted he was involved in several battles. Yesterday fbi agents arrested him at the airport. Today he was in court. Bashar al assad, your days are numbersed. Reporter: He said the group he was with was designated as terrorists. Tonight the charges against him, using the rpg, outside the united states.

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